Research methods - reliability

Reliability - we need to be able to measure/observe something time after time and produce the same or similar results.

EXTERNAL reliability
Measures consistency from one occasion to another - results should be found on different days, different labs, observations or interview by different researchers. To test this - test/ retest- ppts take same test on different occasions.

INTERNAL reliability
Measures the extent to which a test or procedure is consistent within itself, e.g, questions in an interview should all be measuring the same thing. To improve this - split half - compare ppts performance on two halves of a test or questionnaire - should be close correlations on both halves of the test.